Lame delegation to server with cached NS data.

Jonathan de Boyne Pollard J.deBoynePollard at Tesco.NET
Thu Nov 18 04:43:12 UTC 2004

TD> While this is more of a DNS question than a BIND question [...]

... and thus belongs in a different newsgroup ...

TD> As far as I understand it that means the name server is
TD> sending out the request for a question it already has the answer too
TD> thereby creating a loop. Would that be correct?

No.  It's a lot simpler than that.  The "ca." content DNS servers 
delegate "" to the two content DNS servers at 
and  In its turn, the "" content DNS server 
at delegates "" to and back to
itself.  That's the loop.

TD> "Probable cause is lame delegation to server with cached NS data"

And that's precisely what is happening in this case.  The 
"" content DNS server at is vainly trying to 
wear all of the hats at once, and provide proxy DNS service as well as 
content DNS service (when it should really be configured to provide only 
the latter).  It only knows about the "" delegation in the 
first place because at some point, less than a day ago, someone used it 
for proxy DNS service and caused it to look the delegation up. 
Eventually, the delegation information will expire from its cache, and 
instead of publishing a self-referral (in answer to "*" 
questions) it will start publishing a *backwards* referral, for either 
"ca." or ".", until the next time that someone comes along and uses it 
for proxy DNS service to look up something in "".

TD> How can I educate this customer that the 'problem' in question does
TD> not exist on our network but his network layout?

Depending from who your customer actually is, the problem may not be 
anything to do with your customer, either.

The people who need to fix things are the owner of the content DNS 
server at and the owner of "".  The latter 
needs to talk to the former, and persuade/pay him/her to configure 
his/her content DNS server to hold the "" DNS data in its 
database and to publish them.

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